Environment-Mapped Bump Mapping (EMBM)

Definition - What does Environment-Mapped Bump Mapping (EMBM) mean?

Environment-mapped bump mapping (EMBM) is an advanced bump mapping technique that is applied using a combination of different maps. It requires a texture map, bump map and an environment map. A bump is simulated by changing the lighting in areas of the surface on which the bump is located. The bump map contains a value for texel coordinates found on the texture map. The bump map and environment map are combined and the resulting shifted environment map is applied to the original texture.

Techopedia explains Environment-Mapped Bump Mapping (EMBM)

Environment-mapped bump mapping is a technique that will allow for a higher level of detail to be added than what is possible with texture-mapped polygons by themselves. EMBM makes environment mapping possible in multiple and even all directions.

EMBM has some advantages over regular bump mapping:

It accommodates multiple light sources in a single pass together with reflective environment mapping on the same bump. All of these become part of the environment that is being mapped on the bump.

Unlike the multipass alpha technique, EMBM is done per pixel rather than per polygon. The bump map does not change in every frame; it is nonrestrictive and therefore easier for developers to implement.

EMBM can be used for dynamic bumps like water effects or reflections moving with fluidity and realism even with a polygon count of only a few polygons.